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Definition1

cour [koor]noun

One of the four conventional three-month periods of television broadcasting in Japan (January to March; April to June; July to September; October to December): "Noragami" aired during the first cour of 2014.

A portion of a television program aired over the course of one cour1: The big reveal at the end of the first cour of "Valvrave" had me on the edge of my seat!

Usage

I'm really not sure how long "cour" has had currency in English. There are attestations from at least as early as 2007.2 I think that's not too long after the term began to see usage in English-speaking anime communities, but I could very well be mistaken.

This term was probably quickly adopted because it provides an unambiguous way to refer to a roughly 13-episode block of episodes, by contrast with "season", which (as seen here) can mean many different things in different contexts.

A cour is not of precisely-defined duration, and can, in practice, last anywhere from 11 to 14 weeks (and hence, the same number of episodes), though 12-13 weeks is most common, since a 52-week year cleanly divides into four 13-week subunits (or perhaps 12-week subunits with a week off in between).

Etymology

This usage of the word "cour" in English is (perhaps surprisingly) a borrowing of the Japanese word クール (kuuru), which means essentially the same thing as the English "cour".

Japanese kuuru is itself a borrowing, though the language of origin is not known with certainty. The most popular hypothesis is that it derives from French cours, cognate to "course" as in "lecture".3 Note that the English "cour" is effectively a back-formation from cours (which is singular in French), and the singular/plural distinction between "cour" and "cours" is an English innovation.

In any case, the path "cour" took on its way to English is decidedly opaque, and so it is no surprise that it doesn't show up in English dictionaries.

Derived jargon

A split-cour show is one which has a total duration of two cours, arranged such that the show airs for one cour, is on break for the next cour, and airs again in the following cour. Unlike ordinary multi-season shows, which typically incorporate a larger gap between airings and in which each season is produced separately, split-cour shows are produced as a single unit that just happens to have a 3-month break at the halfway point.

Split-cour shows with cour structures other than on-off-on do exist. For example, Ushio to Tora (2015-16) aired as on-on-off-on, for a total of 3 cours of anime over 4 cours of time.

The "second season" of Durarara!!, subtitled ×2, is the first example of a "triply-split-cour" show, with cours airing in winter 2015, summer 2015, and winter 2016. No consensus has yet emerged as to what to call shows like Durarara!!×2 that have multiple splits.

1 The definition at top is my own creation, but I do believe it to be correct and reflective of the way the word "cour" is used in practice. I guess it's good enough for Wiktionary?

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